Hydrodynamic bladed wheel assemblies



March 15, 1966 c. N. SCHRADER 3,240,153

HYDRQDYNAMIC BLADE-D WHEEL ASSEMBLIES Filed Dec. 28. 1961 4 Sheets-Sheetl INVENTOR Carl N. Schroder March 15, 1966 c. N. SCHRADER 3,240,153

HYDRODYNAMIC BLADED WHEEL ASSEMBLIES Filed Dec. 28. 1961 4 Sheets-SheetZ INVENTOR Corl N. Schroder ATTORNEYS March 15, 1966 c. N. SCHRADERHYDRODYNAMIC BLADED WHEEL ASSEMBLIES 4 Sheets-Sheet 5 Filed Dec. 28.1961 Carl N. Schroder ZTTORNEYS March 15, 1966 c. N. SCHRADERHYDRODYNAMIC BLADED WHEEL ASSEMBLIES 4 Sheets-Sheet 4.

Filed Dec. 28. 1961 INVENTOR.

Curl N. Schroder United States Patent filice 3,240,153 Patented Mar. 15,1966 3,240,153 HYDRQDYNAMIC BLADED WHEEL ASSEMBLIES Carl N. Sehrader,Trenton, MiciL, assiguor, by mesne assignments, to Rockwell-StandardCorporation, a corporation of Delaware Filed Dec. 28, 1961, Ser. No.162,872 15 Claims. (Cl. 103115) This application is acontinuation-in-part of my copending application Serial No. 79,040 filedDecember 9, 1960, now abandoned.

The present invention relates to hydrodynamic drives of the fluidcoupling or torque converter type and more particularly to improvedconstructions of bladed fluid torque transmitting wheels in hydrodynamicdrives and also to the method of making and assembling the components ofsuch bladed wheels.

Bladed wheel assemblies of hydrodynamic devices are customarilyconstructed with an outer semi-toroidal annular shell, an innersemi-toroidal core ring, and a set of curved vanes or blades held inplace between the outer shell and inner core ring to transmit arotational force from one wheel to the other by means of a fluid medium.

Prior to the present invention, the manufacture and assembly ofhydrodynamic bladed wheels was achieved in a variety of ways. In one ofthe more widely practiced prior art methods of manufacture, the core andshell are stamped or cast and the blades are assembled in position bymeans of tabs formed integral with the blades. The tabs are fitted intocomplementary slots formed in the core and the shell to locate theblades between the toroidal members in such position as to achieve thedesired direction of fluid flow. By bending the tabs over on the outerside of either the shell or core, or both the core and shell, the bladesare fixed in position. Such tabbed blades are generally fabricated fromsheet metal to readily enable the tabs to be fitted into theirrespective securing slots and bent in locking position.

In another prior method of manufacturing bladed wheels, the blades arecorrectly located between the outer shell and core ring by holding theassembly in a fixture and spot welding or brazing the blades to theouter shell and core ring.

In other conventional methods of assembly and tabrieation, the bladesand outer shell or blades and core ring are formed as an integral unitas by die casting and the remaining toroidal member, whether it be theshell or core ring, is then welded, brazed or cast on to thesub-assembly. In torque converters, the impeller, turbine or reactionmembers have been made of a number of separate segments with eachsegment being die cast and having one or more blades cast integral withparts of the outer shell or inner core or both. The separate segmentsare assembled together by suitable wellknown means such as lock rings.

In the hydrodynamic wheel assemblies embodying separate sheet metalblades having integral tabs for cating and securing the blades in place,several difiiculties have been encountered. To this end, it will beappreciated that due to the inherent flexibility of the sheet metal, theblades are subjectable to distortion during assembly, especially whenthe tabs are bent over and lockingly secured to the shell or core. As aconsequence, the critical blade curvature is change to correspondinglyaffect the torque multiplying characteristics or the torque transferringcharacteristics of the hydrodynamic drive, thus diminishing theefficiency of the drive.

Furthermore, a substantially large number of tabbed sheet metal bladesare usually required in fluid wheel assemblies in order to absorb fluidimpact loads and to effectively direct the flow of fluid. In addition,it was not possible to interchange one set of tabbed blades with bladeshaving a different curvature because of the fixed tab and slot locationsin the assembly.

Integral cast wheel assemblies, either cast as a whole or in segments,are quite expensive to make because of the intricate coring required toform the various parts. Die casting the fluid wheels as an integral unithas generally been -found to be economically unacceptable andimpractical because of the complex shapes of the curved blades whichrequire several dies and cores, thus making the cost of manufactureprohibitive. Furthermore, in torque converters, either the turbine orimpeller is usually drivingly attached to separate hub members or thelike, thus requiring cost-consuming bolting or welding to secure the hubmember to the shell of the turbine or the impeller.

From the above considerations, it is apparent that, heretofore, therehave been no satisfactory hydrodynamic bladed wheel constructions ingeneral use which are simple and economical to make and to assemble andwhich, at the same time, provide for a rigid vibrationproof bladed Wheelstructure. Accordingly, the present invention contemplates and has asits primary purpose a hydrodynamic bladed wheel of improved constructionwhich satisfies these foregoing requirements and which is readily madeand easily assembled.

This is essentially accomplished according to the present invention byproviding for an outer shell having integral rigid posts on whichhollowed blades are mounted and held in their proper oriented positionsby securing an inner core ring to the mounting posts. The bladesaccording to the present invention are tightly but non-interlockinglyheld between the core and shell with the blades engaging the core andshell only along separable abutment surfaces. In contrast to thecommercially acceptable hydrodynamic drive constructions heretoforeknown, the blades of the present invention are not fixed or interlockedto either the shell or the core ring but rather engage the shell and thecore ring only along non-interlocking separable abutting contactsurfaces to thereby provide a simplified method of manufacture.

To further reduce manufacturing costs, the present inventioncontemplates the provision of a hydrodynamic wheel assembly in which theouter shell is cast integral with a splined or geared drive hub memberor like drive attachment member, thus eliminating expensive bolting orwelding.

With the foregoing considerations in mind, one of the primary objects ofthe present invention is to provide a novel bladed wheel assembly havingan outer shell formed integral with mounting posts over which hollowblades are placed in proper position and held in place by an innershroud or core ring secured to the posts.

Another object of the present invention is to provide a novelhydrodynamic bladed wheel having an outer shell cast integral with adriving hub or the like which may be conveniently machined prior toassembly with the other components of the wheel.

A further object of the present invention resides in the provision of afabricated or cast hydrodynamic bladed wheel assembly in which theseparate members are assembled in a manner to enable the selective useof difierent combinations of a variety of materials in the manufactureof the assembly. With the present invention, for example, the outershell may be made from ductile iron, malleable iron, aluminum ormagnesium and assembled with an inner core ring made from the samematerial or any of the other materials mentioned above. The blades maybe made from steel, aluminum, magnesium or plastic and assembled with acore ring and shell made from any combination of the materials mentionedabove. Thus, it is evident that the shell, core ring and blades may bemade from different materials to provide an expanded versatility indesign from light to heavy range depending on the applicationrequirements.

Another object of the present invention is to provide for a novelhydrodynamic bladed wheel construction in which the blades are fixedlyclamped in non-interlocking separable surface abutting relationshipbetween separately formed blade supporting shell and core sections.

A further object of the present invention is to provide for a novelmethod of manufacturing a hydrodynamic bladed wheel structure havingseparately fabricated component parts which are easily made and readilyassembled.

Another object of the present invention is to provide for a novelhydrodynamic bladed wheel construction having separable blades, an outershell and an inner core ring with the core ring being pulled up snuglyin non-interlocking abutment with the blades and fastened in place onlyby means on the shell so as to clamp the blades in a fixed orientedposition between the shell and core ring.

A further object of the present invention is to provide a novelhydrodynamic bladed wheel construction in which the blades aredetachably interchangeable to provide for different torquemultiplication ratios or to facilitate ready replacement of damaged orbroken parts.

Another object of the present invention is to provide for a novelhydrodynamic bladed wheel construction which has simplicity ofconstruction and which has a low manufacturing cost.

Still a further object of the present invention resides in the provisionof hollow blade members for a hydrodynamic wheel assembly made as anextrusion casting, forging or formed sheet metal from materials such asplastics or aluminum and having smooth and durable surfaces to beextremely sensitive to oil flow. The hollow blade members may be madeheavy or light although retaining their outside dimensions and curveconfiguration.

Further objects of the invention will appear as the description proceedsin connection with the appended claims and the annexed drawings wherein:

FIGURE 1 is a simplified longitudinal sectional view of a hydraulictorque converter embodying bladed, impeller and turbine wheels made inaccordance with the present invention;

FIGURE 2 is an enlarged sectional fragmentary perspective view of thebladed impeller wheel illustrated in FIGURE 1;

FIGURE 3 is an enlarged fragmentary partially sectioned perspective viewof a bladed impeller wheel according to a further embodiment of thepresent invention;

FIGURE 4 illustrates one form of a hollowed blade utilizable in thehydrodynamic bladed wheels according to the present invention;

FIGURE 5 is a fragmentary front elevational view of a bladed impellerwheel according to still another embodiment of the present inventionwith a portion of the inner core ring being broken away to show detailsof the blading and blade mounting structure;

FIGURE 6 is-a section taken along lines 66 of FIG- URE 5;

FIGURE 7 is an enlarged sectional view taken substantially along lines7-7 of FIGURE 5;

FIGURE 8 is a section similar to that of FIGURE 7 but showing a modifiedform of the blade structure;

FIGURE 9 is a section similar to that of FIGURE 7 but showing a furthermodified form of blade structure;

FIGURE 10 is a section similar t that of FIGURE 7 but showing a modifiedform of the blade and the blade mounting post structure;

FIGURE 11 is a fragmentary front elevational view of a bladed wheelaccording to still another embodiment of the present invention andillustrating a portion of the inner core ring broken away to showdetails of the blades and the blade mounting structure;

FIGURE 12 is a cross-section taken substantially along lines 12-12 ofFIGURE 11;

FIGURE 13 is a fragmentary perspective sectional view illustrating abladed wheel according to a further embodiment of the present invention;

FIGURE 14 is a fragmentary perspective view of a bladed wheel similar tothat of FIGURE 13 and illustrating still another embodiment of thepresent invention;

FIGURE 15 is a section taken substantially along lines 15-15 of FIGURE11;

FIGURE 16 is a section similar to that of FIGURE 15 and illustrating amodified form of blade construction; and

FIGURE 17 is a section similar to FIGURE 15 and illustrating a modifiedform of the blade and mounting post structure.

Although the present invention is illustrated and described to beembodied in a single stage, two phase torque converter for use withautomotive power transmissions, it will be appreciated that the bladedwheel structures to be presently described in detail may also beincorporated into any hydrodynamic coupling device.

Thus, with reference to the drawings and more palticularly to FIGURES 1and 2, the reference numeral 20 generally designates a hydrodynamicbladed wheel assembly embodying the principles of the present inventionand constructed as a bladed impeller for incorporation into a torqueconverter indicated at 22 in FIGURE 1. Torque converter 22 includes abladed turbine 24 driven by the energy produced by impeller 20, and aconventional bladed reaction member 26 mounted between impeller 20 andturbine 24 on a conventional one way clutch unit 28 in the manner shown.

Driving torque is transmitted to impeller 20 by means of an impellerdriving flange or turbine cover 30 which is coupled to a drive shaft 32.Shaft 32 is drivingly connected to an engine output shaft (not shown)for rotating impeller 20. By rotation of impeller 20, energy istransmitted to fluid circulated in a toroidal passageway 34 in which theblades of impeller 20, turbine 24 and reaction member 26 are disposed,to rotate turbine 24. Turbine 24 is coupled to a drive hub 36 which issecured to a transmission input shaft 38 extending through the casing ofconverter 22 for connection to a mechanical transmission (not shown).Shaft 38 rotatably extends through a sleeve 40 upon which clutch unit 28is mounted.

In describing the construction of impeller 20 and the various modifiedforms of hydrodynamic bladed wheel assemblies according to the presentinvention, it is understood that the construction and method forcarrying out manufacture and assembly of the component parts of thebladed wheel assembly may be equally applied to turbine 24 or to otherforms of bladed wheel assemblies utilized in hydrodynamic drive devices.

As is well known, the blades of the fluid wheels in torque converter 22or other hydrodynamic devices are required to be formed with a complexhydro-foil shape in order to efiiciently circulate the converter fluid.This complex curvature of the blades constitutes one of the main reasonsfor the difficulties previously encountered in making the blades andalso in assembling the blades with the supporting inner and outer shroudmembers of the bladed wheel assembly. Due to the complex curved contourof the blades, integral casting of hydrodynamic bladed wheel assembliesis economically impractical with prior art methods of manufacture. Withknown methods of manufacture, the blades could not always be proper! lylocated and adequately supported with respect to the toroidal path offluid flowing through passageway 34 of torque converter 22. It has beenfound that reaction forces due to the fluid flow direction change aregreatest in the region of maximum flow deviation. This region can beapproximately located along a line bisecting the entrance and exit angleof the blade and constitutes one of the weakest points in former bladedwheel constructions. The present invention overcomes the foregoingshortcomings of prior art constructions and methods of manufacture aswill become apparent as the description proceeds.

With reference now to FIGURE 2, impeller 20 is shown to comprise ahollow outer annular shell 44 of semi-toroidal shape, a hollowed annularinner core ring 46 of semi-toroidal shape and a set of circumferentiallyspaced apart blades 48 fixedly secured between core ring 46 and shell44. Shell 44 and core ring 46 are separately formed as one-piecestructures and may be die cast or forged. Shell 44 and core ring 46 maybe made from any material suitable for a preferred application,including aluminum and thermal plastic materials. By casting shell 44and core ring 46 separately according to the present invention, it willbe appreciated that the intricate coring required in casting the shelland core ring as one piece is obviated.

With continued reference to FIGURES 1 and 2, shell 44 is formed with aninwardly directed concave surface 49 facing core ring 46 and delimitingpassageway 34. Core ring 46 is arranged radially and axially inwardlywith respect to shell 44 and is formed with a convex surface 50 facingsurface 49 in spaced relation thereto and delimiting passageway 34. Asshown, core ring 46 is hollowed to form an endless channel 51 openingaxially outwardly in a direction facing away from shell 44.

As shown in FIGURES 2 and 4, each of the blades 48 is of hollowedthree-dimensional curved construction to provide a passage 52 extendingcompletely through the blade. Blades 48 may be fabricated from sheetmetal or they may be cast with the hollowed form from suitable lightweight materials such as aluminum, magnesium or thermo-plastics.

Blades 48 may be hollow throughout, thus providing only a relativelythin outer wall to save material and weight. Where a more rigidpositioning of blades 48 is required for heavier torque loadapplications, however, a substantially solid blade is provided with arelatively narrow bored or cored passage to facilitate assembly of theblades, in a manner as will be presently described.

To properly secure and locate blades 48 within the assembly of componentparts forming impeller 20, shell 44 is integrally formed with aplurality of blade mounting posts 56 equiangularly spaced apart along acommon radius. Posts 56 rigidly project axially inwardly from acontinuous circumferential ledge portion 58 formed integral with shell44 and protruding inwardly from the inner concave shell wall surface 49as shown. The number of posts 56 provided for correspond to the numberof blades 48.

Posts 56 are generally conical in shape, being tapered to convergeinwardly toward their outer tips. The tip of each post 56 is providedwith a recess 64 extending axially inwardly along the longitudinal axisof the post to provide a thin walled annular tip portion 66 for apurpose as will presently appear. Core ring 46 is provided with aplurality of equiangularly spaced apart apertures 68 arranged along acommon radius and registering with posts 56 to receive the recessed tipsthereof in the manner shown.

In the assembly of the shell, core ring and blade components of impeller20, the hollowed blades 48 are slidably mounted on posts 56 within outershell 44 in such a manner as to properly orient blades 48 to achieve adesired direction of fluid flow through passageway 34. The inner andouter edge surfaces of blades 48 are re- 6 spectively formed toabuttingly match the curvature of the convex surface 50 of core ring 46and of concave surface 49 or shell 44 such that blades 48 snuglyabuttingly inertfit with shell 44 and core ring 46 along smoothseparable surfaces. Blades 48 are recessed at 70 to interfittinglyreceive ledge portion 58 in the manner shown.

As shown in FIGURE 2, the wall surface of passage 52 formed in each ofthe blades 48 snugly engage the smooth tapered sides of the respectiveposts 56 extending therethrough. Thus, in the oriented positions ofblades 48 on posts 56, blades 48 are in interfitting noninterlockingseparable surface abutment with shell 44 and core ring 46.

With continued reference to FIGURE 2, location tabs 74 may be formedintegral with blades 48 preferably protruding from a blade edge 76 inspaced relation to passage 52 to more readily locate the blades duringthe assembly of the component parts of impeller 20. Tabs 74 areinterfittingly but non-interlockinly received in equiangularly spacedapart recesses 78 formed inwardly of the interior concave periphery ofshell 44. In some instances, location tabs may be provided on the bladeson either the leading edge or trailing edge or both, or on either sideof the blades to locate them during assembly of the component parts ofimpeller 20.

After blades 48 are slidably mounted on posts 56, core ring 46 is thenmounted in the assembly by freely fitting apertures 68 over the tips ofposts 56 and by positioning core ring 46 in snug separable surfaceabutment with the inner blade edge surfaces indicated at 80 so that theti s of posts 56 project through apertures 68 and into channel 51 in themanner shown.

Core ring 46 is secured to shell 44 with blades 48 fixedly clampedbetween core ring 46 and shell 44 by deformably flaring the thin walledtipped portion 66 outwardly to thereby secure core ring 46 to posts 56and thus provide a rigid and unitary tightly interlocked assembly ofshell 44, blades 48 and core ring 46.

As shown in FIGURE 2, washers 82 of suitable thickness may be fittedover the tips of posts 56 between the flared wall portions 66 and theconcave interior wall surface of core ring 46 to compensate forVariations in manufacturing tolerances, thus assuring that core ring 46is held tightly and snugly against the inner edge surfaces of blades 48.

It is known that the efficiency of hydrodynamic fluid coupling devicespredominantly depends on the curvature of the blades and theirrespective positions in the fluid medium passageway. Another importantrequirement contributing to effectively high efiiciency is that theblades be securely held in place and positively fixed between the outershell and inner core ring to obtain satisfactory torque multiplicationratios and to absorb the impact of the circulating fluid impingingagainst the blades to transmit power. Most stresses and strain areexerted at the entrance and exit end of the blades and it is thereforeimperative that the blades be securely held against rotation ordistortion by the circulating fluid which is forced in a toroidal paththrough the passages defined by the spaces between the blades.Furthermore, it is desired to prevent rattle and vibration in theassembly as well as keeping the assembly as light as possible to reducethe weight of the rotating masses which create centrifugal forces.

As already mentioned, it is very diflicult in prior hydrodynamic devicesto meet all of the above requirements without sacrifices in cost orefficiency. The present invention enables blades 48 to be made of alight weight material such as, for instance, magnesium, aluminum,plastic or formed from sheet metal with a three-dimensional shape. Withthe present invention, the three-dimensional blade member whether solid,entirely hollow or partly hollow withstands greater forces and bendingstresses than a single walled sheet metal blade. This is true during theoperation of the hydrodynamic device as well as during assembly of theseparate members.

With the present novel construction and assembling method, distortion ofthe blades is elfectively prevented. In contrast to other prior devices,the blades themselves are not secured to either the outer shell or corering, but instead the core ring is secured only to the outer shell bymeans of the integral posts which extend through the blades with theblades merely being clamped between the outer shell and inner core ring.To prevent the blades from rotation or displacement due to the fluidimpact, blade location tabs as shown in FIGURES 12-14 may be providedfor and the passages through the blades are shaped to closely fit aroundthe posts. Alternatively, the posts may be setv at an angle as shown inFIGURES and 17.

By fabricating blades 48 separately from shell 44 and core ring 46,light weight mate-rial such as sheet metal maybe readily utilized informing the blades to reduce the moment of inertia of the rotatingcomponents of the impeller. It further will be appreciated that blades48, being in engagement with core ring 46 and shell 44 only alongnon-interlocking separable abutting contact surfaces, are readilyinterchangeable with blades of different materials or curvatures simplyby removing core ring 46 and sliding blades 48 011 posts 56. As blades48 are not permanently fixed to either core 46 or to shell 44 as by weldspots, locking tabs or casting, there is no damage to the blades inremoving them from the hydrodynamic bladed wheel assembly so that theblades which are removed from one assembly may be readily re-used inother assemblies.

With continued reference to FIGURES 1 and 2, shell 44 is cast or forgedintegral with an elongated hub 84 formed with a through bore 85 andhaving a machined internal set of splines 86 and a machined external setof gear teeth 88. Gear teeth 88 are adopted to transmit torque fromimpeller for driving auxiliary equipment (not shown). By means of theset of splines 86, impeller 20 is splined to a secondary drive shaftsleeve 90 extending through bore 85 and being rotatably mounted on shaft38 in the manner shown. Depending upon the specific application oftorque converter 22, either splines 86 or gear teeth 88 may be omitted.Hub 84 extends axially rearwardly from the body portion of shell 44containing surface 49.

The foregoing outer shell structure having an integrally cast drive hubeliminates the necessity of attaching a separately formed hub member bycostly bonding or bolting arrangements.

FIGURE 3 illustrates another embodiment of a bladed impellar wheel inwhich the blade mounting post structure is modified. As shown in FIGURE3, posts 56 and ledge portion 58 of FIGURE 2 are replaced by a pluralityof equiangularly spaced apart blade mounting posts 100 formed integralwith outer shell 44 and extending generally axially inwardly toward corering 46 from the inwardly facing concave surface of shell 44. Posts 100are spaced along a common radius and are each formed with substantiallyflat sides and opposed radially extending tapered edges indicated at 102which converge toward the tip of the post. The tip of each of the posts100 is provided with a V-shaped notch located approximately midwaybetween the opposed edges 102 and extending inwardly from the tip of thepost to form side-by-side spaced apart tangs 104 and 106 for a purposeas will presently appear. The number of posts 100 correspond to thenumber of blades embodied in the assembly.

With continued reference to FIGURE 3, core ring 46 is formed with aseries of equiangularly spaced apart slots 110 which register with posts100. A set of hollowed blades 1 1 1 are slidably mounted one on each ofthe posts 100. Blades -111.are essentially identical in construction toblades '48 except that the recess 70 is omitted and the 8 passageextending through each blade is shaped to interfit with posts 100.

To fixedly secure core ring 46 to posts 100, with blades 11 1 clampedsnugly between core ring 46 and shell 44, the tips of posts extendthrough slots and the tangs 104 and 106 are bent over in oppositedirections to abuttingly engage the concave interior surface of corering 46, as indicated at 112 to snugly engage and lock core ring 46 inposition on posts 100.

To assemble the component parts of the impeller wheel illustrated inFIGURE 3, blades 111 are slidably mounted on posts 100 in outer shell 44and may be properly positioned by fitting blade tabs 74a into recesses78a in the same manner as described in the embodiment of FIGURE 2. Corering 46 is then mounted on posts 100 in abutment with blades 111 andwith the tips of posts 100 extending through slots 110 such that tangs104 and 106 are disposed on the side of core ring 46 facing away fromshell 44. To lock core ring 46 to outer shell 44 and thereby clampinglysecure blades 111 in place, tangs 104 and 106 are bent over in oppositedirections to abut the concave surface of core ring 46 facing away fromshell 44, thus providing a tightly fitted bladed wheel assembly.

In the embodiment of FIGURES 5-7, modified forms of blade, mounting postand hub constructions are illustrated. With continued reference toFIGURES 5-7, a set of blades 119 are positioned on conically shaped,equiangularly spaced apart posts 120 formed integral with outer shell 44and extending axially inwardly toward core ring 46 in the same manner asdescribed in the embodiments illustrated in FIGURES 2 and 3.Alternatively, blades 48 may be mounted on posts 120 in place of blades119.

Posts 120 are spaced along a common radius and extend through ellipticalslots 126 formed in core ring 46. The tips of posts 120 extending beyondthe concave surface of core ring 46 facing away from shell 44 areflared, upset or otherwise distorted to tightly lock core ring 46 toouter shell 44 in snug abutment with blades M9 to securely butnon-interlockingly clamp blades 119 in place, thus providing a shock andrattle proof fluid wheel assembly.

As shown in FIGURE 7, each of the blades 119 is provided with a straightthrough passage 127 and is generally rectangularly shaped incross-section except for oppositely facing side portions 128 and 129which are inclined at an acute angle with respect to the longitudinalaxis of passage 127. Side portions 128 and 129 respectively face towardand away from the direction of wheel rotation as indicated by the arrow.Side portion 128 forms with an oppositely facing side portion 130 anenlarged blade region indicated at 131. Similarly, side portion 129forms with an oppositely facing side portion 132 an enlarged bladeregion indicated at 133. Side portions 130 and 132 are parallel incross-section and merge respectively with side portions 128 and 129.Thus, blade 119 is widest at its oppositely facing ends respectivelyabutting core ring 46 and shell 44 and gradually reduces to minimizethickness at a region approximately midway between its ends. This bladeconstruction improves the stability of the blade and post assembly.

With continued reference to FIGURES 57, posts 120 extend along axeswhich are parallel to the axis of wheel rotation. Posts 120 matinglyextend through passages 127 in coaxial relationship therewith. Each ofthe posts 120 is formed with a widened base portion 134 disposedadjacent to the concave surface of shell 44 and merging with arelatively slim pillar portion 135. Base portion 134 is formed with aninclined side 135a facing in the direction of wheel rotation andextending at an acute angle with respect to the longitudinal axis of thepost. With this structure, the thickness of post 120 is Widestimmediately adjacent to shell 44 where the post enters its blade 119 andgradually becomes narrower in a direction extending toward pillarportion 135. This construction of post 120 reinforces the structuralstrength of the post and blade assembly at a region where theconcentration of stress is greatest.

With continuing reference to FIGURES and 6, outer shell 44 is formedintegral with a hub 136 having a smooth cylindrical bore 137 and aradially extending annular recess 138 opening into bore 137approximately midway between opposed end faces of hub 136. In assemblyof the bladed hydrodynamic wheel illustrated in FIGURES 5 and 6 in ahydrodynamic device, the outer shell is arranged to be drivinglyconnected to a drive shaft member (not shown) by a split ring 138areceived in recess 138.

In the assembly of the component parts of the bladed wheel illustratedin FIGURES 5-7, blades 119 are slidably mounted over posts 1211 andarranged in their properly oriented positions. Core ring 46 is thenmounted on posts 120 with the tips of posts 120 extending through slots126 in the manner shown with core ring 46 snugly abutting and pulledtightly up against blades 119. The tips of posts 120 extending throughslots 126 are then flared, upset or otherwise distorted to tightly lockcore ring 46 to outer shell 44 with blades 119 securely clamped betweenshell 44 and core ring 46 in the manner similar to that described in theembodiments of FIGURES 2 and 3.

FIGURE 8 illustrates a modified form of blade structure which isessentially the same as that shown in the embodiment of FIGURES 57except that four fillets indicated at 139 are added to the integralstructure of blades 119 already described. Fillets 139 are concave inshape and are disposed at the corners of blade 119 abutting core ring 46and shell 44 with their concave surfaces facing into toroidal passageway34. This fillet structure assures a smooth uninterrupted oil flow inpassageway 34.

FIGURE 9 illustrates another modified form of the blade structure forincorporation into the core and shell assembly shown in FIGURES 5-7. Inthis embodiment of FIGURE 9, a hollowed blade 141 is mounted on each ofthe posts 120 with each post extending completely and coaxially througha straight passage 142 formed in the blade. As shown, the cross sectionof blade 141 contained in a plane passing through the axis of passage142 is generally in the shape of a parallelogram having oppositelyfacing sides 144 and 146. Sides 144 and 146 are inclined in thedirection of wheel rotation (as indicated by the arrow) and at an acuteangle with the longitudinal axis of post 120. Side 144 terminates at theentrance to passage 142 with the entrance of the blade passage beingcontained in a plane extending at an acute angle to the longitudinalaxis of post 120 to expose a portion of post 120 indicated at 147 andfacing generally oppositely from the direction of Wheel rotation. Side146 terminates at the exit of passage 142 with the exit being containedin a plane extending at an acute angle to the longitudinal axis of post120 to expose a portion of post 120 indicated at 148 and facing in thedirection of wheel rotation.

With this blade construction of FIGURE 9, post 120 enters blade 141 nearthe end of side 144 adjacent a shell 44 and leaves blade 141 near theend of side 146 adjacent to core ring 46.

FIGURE illustrates another mounting post and blade construction in whichshell 44 is provided with a series of equiangularly spaced apart blademounting posts 149 extending generally axially inwardly from theinwardly directed concave surface of shell 44 along a commoncircumference. Each post 149 is horizontally inclined at an acute anglewith respect to the axis of wheel rotation such that each post slopesaway from the direction of wheel rotation.

Mounted on each post 149 is a blade 152 of hollowed construction forminga straight passage 154 through which post 149 matingly extends. Thecross section of blade 152 contained in a plane passing through the axisof passage 154 is substantially in the shape of a parallelogram havingoppositely facing sides 156 and 158. Sides 156 and 158 are inclined atan angle coinciding with the angle at which post 149 and passage 154 areinclined. Passage 154 is centered with respect to sides 156 and 158 toprovide equal blade thicknesses on both sides of post 149 in the mannershown. Blades 152 are provided with a fillet 160 disposed at each of thecorners of the blade and facing into passageway 34 in the same manner asdescribed in the embodiment of FIGURE 8.

In the embodiment of FIGURE 10, the posts 149 are not widened at theirbases since the inclination of posts 149 provides sufficient strength.

With continued reference to FIGURE 10, each post 149 of the bladed wheelassembly extends through apertures 164 formed in core ring 46 with corering 46 being fixedly secured to posts 149 as by flaring or otherwisedistorting the tip of each post extending axially beyond the inwardlydirected surface of core ring 46 in the same manner as described in theembodiment of FIGURE 7. The assembly of the bladed wheel shown in FIGURE10 is accomplished in the same manner as described in the previousembodiments.

FIGURES 11 and 12 illustrate another bladed wheel construction in whichthe shell and core ring components are stamped or otherwise formed fromsheet metal instead of casting these component parts in the mannerdescribed in the previous embodiments.

With continued reference to FIGURES 11 and 12, the reference numeraldesignates an inner shell stamped or otherwise formed from sheet metal.Shell 170 is provided with a semi-toroidal body portion 172 which isgenerally dished shaped to form an endless channel opening axiallyinwardly.

With continued reference to FIGURES 11 and 12, a sheet metal annularouter shell member 174 is stamped or otherwise formed with a dishedshaped body portion 176 which interfittingly abuts the outwardlydirected convex surface of shell 170. Shell 179 is disposed axiallyinwardly of member 174 and is rigidly fixed to member 174 as by spotwelding indicated at 181).

With continuing reference to FIGURES l1 and 12, a series of relativelyflat sided tapered tangs 182 are stamped out of body portion 176 and arebent axially inwardly at right angles to a plane passing perpendicularlythrough the rotational axis of the bladed Wheel in the manner oest shownin FIGURE 15. Tangs 182 are equiangular-ly spaced apart around a commonradius and extend axially inwardly through apertures 184 formed in shell170 (FIG- URE 15). By forming tangs 182 and bending them over, apertures186 are formed in body portion 176 of member 174 as best shown in FIGURE15.

T angs 182 take the place of the blade mounting posts described in theprevious embodiment and are equal in number to the number of blades tobe mounted in the bladed wheel assembly.

Slidably mounted on each of the tangs 182 is a hollowedthree-dimensional blade 188 which is substantially of the sameconstruction as blades 119 illustrated in FIGURES 5-7. The cross sectionof blades 188 in a plane passing about midway between the oppositelyfacing edges of tangs 182, however, in more of a parallelogram in shapewith each tang entering at one corner of the blade and leaving at thediagonally opposite corner of the blade. Blades 188 may be cast fromlightweight metal or plastics.

To properly locate blades 188 in the assembly, the blades are providedwith integral narrow projections 192 (FIGURE 12) adjacent to the thinportion of the blades. Projections 192 interfittingly extend intodimpled recesses 193 formed in shell 170 and opening generally radiallyinwardly in spaced relation to tangs 182.

As best shown in FIGURES 12 and 15, the outwardly facing edges of blades188 interfittingly abut the concave surface of inner shell body portion172 with each blade being of such width to completely cover apertures184 through which tangs 182 extend, thus preventing any leakage fromoccurring between blades 138 and the outer shell 174. Apertures 186formed by bending tangs 182 inwardly are sealed by snug interfittingabutment of body portion 172 with body portion 176. By this structure,blades 188 seal off apertures 184 and body portion 172 coacting withbody portion 176 seals off apertures 186 to prevent the escape of fluidfrom the toroidal chamber delimited by shell 170.

With continuing reference to FIGURES ll, 12, and 15, tangs 182 extendaxially beyond the inwardly facing edges of blades 188 and projectthrough apertures 196 formed in an annular dished shaped inner core ring198. Core ring 198 is stamped or otherwise formed from sheet metal andis shaped with an axially inwardly extending endless channel to providea convex surface facing the concave surface of body portion 172 anddelimiting a segmental portion of a toroidal passageway 282 formedbetween core ring 198 and inner shell 178.

Core ring 198 is slidably mounted on tangs 182 with its convex surfaceinterfitting abutting the inner edges of blades 188 in assembledrelation. The tips of tangs 182 project axially inwardly beyond corering 198 and into the channel formed thereby. To fixedly secure corering 198 in place and thus lockingly clamp blades 188 in positionbetween inner shell 170 and core ring 198, the tips of tangs 182extending beyond core ring 198 are mechanically deformed as by riveting,upsetting or bending. As a result, it will be appreciated that blades188 are securely locked in position between inner shell 170 and corering 198 without attaching the blades themselves to either the shell orthe core ring with the core ring being secured solely to tangs 182.

In the embodiment illustrated inFIGURE 13, a thin ring 210 is employedto properly locate blades 188 in assembled relationship on tangs 182 inplace of recesses 193. In this embodiment, body portion 172 of shell 170is provided with a radially outwardly offset end portion 212 extendingrearwardly from its generally axially extending edge indicated at 214and forming a shoulder 216. Ring 2118 is received in the recess formedby offset portion 212 with its radially outwardly directed surface insnug interfitting abutment with a radially inwardly directed surface 218formed on offset portion 212.

Ring 210 is formed with a series of equiangularly spaced apart slots 220formed axially inwardly from the edge facing shoulder 216. Slots 228correspond in number to the number of blades in the assembly andprojections 192 of blades 188 interfittingly extend into slots 220 tothereby locate and secure blades 188 against displacement.

In the embodiment illustrated in FIGURE 14, a resilient fiat-sidedlocking ring 238 is employed to secure core ring 188 in place on tangs182 without deforming the tips of tangs 182. In this embodiment, thetips of tangs 182 projecting beyond core ring 198 are provided withradially outwardly facing slots 232 immediately adjacent to the concaveinner surface of core ring 198.

Locking ring 230 snugly extends into slots 232 with its axiallyoutwardly directed surface in snug interfitting abutment with theinwardly directed concave surface of core ring 198 in the manner shownto thus lock core ring 198 to tangs 182. With this construction, it willbe appreciated that locking ring 238 is sufficiently deformable so thatit may be stretched over the tips of tangs 182 and fitted into slots232. Since locking ring 230 is readily removable, it is clear that corering 198 may be detached from tangs 182 to enable the replacement ofblades 188.

FIGURE 16 illustrates another blade construction in which the referencenumeral 236 generally designates a hollow sheet metal or plastic blademounted on each one of the tangs 182. Blade 236 is made up of twoseparate reversely shaped one-piece sections 238 and 240 bonded orotherwise fixedly secured together. Each of the sections 238 and 248 arestamped with or otherwise formed in cross section with a side portion242 which extends parallel with the rotational axis of the wheel andwhich merges with an inclined portion 244. Inclined portion 244terminates in an end portion 246 which is bent over substantially atright angles to portion 242.

With continued reference to FIGURE 16, portion 242 of section 240matingly and snugly abuts the fiat side face of tang 182 facing awayfrom the direction of wheel rotation and has its outwardly directed edgeinterfittingly abutting the inwardly directed concave surface of bodyportion 172. The inclined portion 244 of section 240 slopes away fromtang 182 at an acute angle and the end portion 246 of section 240 snuglyand interfittingly abuts the outwardly directed concave surface of corering 198. Similarly, portion 242 of section 238 snugly andinterfittingly abuts the surface tang 182 facing in the direction ofwheel rotation with the inwardly directed free edge of portion 242 insnug interfitting abutment with the outwardly directed convex surface ofcore ring 198. The inclined portion 244 of section 238 slopes away fromtang 182 at an acute angle and in the direction of rotation of thebladed wheel assembly. The end portion 246 of section 238 snugly andinterfittingly abuts the inwardly directed concave surface of bodyportion 172.

As shown in FIGURE 16, sections 238 and 240 are secured together one oneach side of its respective tang 182. Sections 238 and 240 form, incross section, a box-like blade of generally parallelogram shape withtang 1'82 entering blade 236 at one corner and leaving blade 236 at thediagonally opposite corner. Sections 238 and 240 of blade 236 cooperateto completely cover the aperture 184 through which tang 182 extends tothereby seal off aperture 184 and prevent leakage of fluid fromoccurring between the blade and the shell assembly.

Referring now to FIGURE 17 in which a modified blade construction isillustrated, the reference 250 generally designates a hollow thinsectioned blade mounted on each of the tangs 182. In this embodimenttangs are not bent completely over at right angles to the direction ofwheel rotation but are rather bent only to an acute angle with respectto the direction of wheel rotation in the manner shown. Theconfiguration of blade 250 is similar to that described in theembodiment of FIG- URE 10.

In all the embodiments of the present invention, only one integral postor tang for each blade is used to mount the blades between the outershell assembly and the inner core ring thus enabling the readysubstitution of blades of different curvatures within the same outershell and core ring. With the previously known structures using multipleblade locking arrangements, the replacement of the blades is notpossible. By interchanging blades of different curvatures, it ispossible to obtain different torque readings by retaining the sameoverall size of the fluid wheel. The separate formation of the wheelmembers eliminates the need for expensive intricate coring in methodsformerly used.

Furthermore, it is feasible to use different materials for each of thethree components for any bladed wheel assembly. For instance, a bladedwheel assembly may have a cast metal outer shell, aluminum or plasticblades and a sheet metal inner core ring.

By choosing any of todays available materials such as steel, ductileiron, malleable iron, aluminum, magnesium or thermoplastics, fabricatedor cast, almost any arrangement is possible due tothe interchangeabilityof the separate component parts making up the bladed wheel. This allowsthe manufacturer .to design heavy or light, depending on the specificrequirements.

Thus, it will be appreciated that the present invention provides afabricated hydrodynamic bladed wheel assembly which can be made atsubstantial reduction in manufacturing costs and which is easilyassembled without distorting the critical curvatures of the cast orformed blades. Because of the unique locking of the inner core ring tothe outer shell, distortion of the critical blade curvature duringassembly is avoided.

The integral construction of the outer shells with their associated hubseliminates the interlocking and expensive bolting arrangements requiredwith prior art assemblies having separate hub members.

The invention may be embodied in other specific forms without departingfrom the spirit or essential characteristics thereof. The presentembodiments are therefore to be considered in all respects asillustrative and not restrictive, the scope of the invention beingindicated by the appended claims rather than by the foregoingdescription, and all changes which come within the meaning and range ofequivalency of the claims are, therefore, intended to be embracedtherein.

What is claimed and desired to be secured by Letters Patent is:

1. A bladed wheel unit for a hydrodynamic fluid torque transmittingdevice comprising:

(a) separate coaxially disposed integral inner and outer annular membersspaced to provide a generally annular space of substantially constantcrosssection therebetween for passage of fluid;

(b) said outer member having an inwardly facing smoothly curvedtransversely concave annular inner passage defining surface and saidinner member having an outwardly facing smoothly curved transverselyconvex annular outer passage defining surface opposed thereto;

(c) said inner member having a series of circumferentially spacedapertures;

(d) a plurality of posts of one-piece construction with said outermember and projecting through said space and through said apertures;

(e) a plurality of separate hollow blades mounted on said posts withinsaid space with the inner and outer ends of said blades shaped totightly and smoothly but separably abut said inner and outer membersurfaces respectively;

(f) cooperating complementary projection and recess means on each saidblade and the adjacent interior of said outer member disposed radiallyoutwardly of said posts in the unit and adapted for direct interfittingengagement during assembly as said posts are pushed slidably throughsaid hollow blades, so that said blades are non-rotatably mounted andlocated in desired relative spacing and orientation within said fluidpassage space;

(g) said blades having end to end through bores fitting snugly andsmoothly over said posts so that the blade and posts assemblies aresubstantially solid throughout; and

(h) said posts being thicker at their bases where they intersect saidconcave surface of the outer member; and

(i) means on the inner ends of said posts and disposed within andcoacting with said inner member for securing said inner member inbridging relation across said inner ends of all of said posts foraxially holding all of said blades rigidly between said inner and outermembers and fastening said members and blades together as a rigid unit.

2. The bladed hydrodynamic torque transmitting unit as defined in claim1, wherein each post has an axially recessed tip formed with a thin wallportion extending axially beyond the surface of said inner annularmember facing away from said outer annular member and being deformedwith respect to its respective post for securing said inner annularmember to said posts in snug abutment with said blades.

3. The bladed hydrodynamic torque transmitting assembly defined in claim2 comprising:

(a) annular means mounted on said posts and disposed between saiddeformed thin wall portion and said inner annular member,

(b) said annular means being of predetermined thickness to compensatefor variations in tolerances in said blades and said inner and outerannular members.

4. The bladed hydrodynamic torque transmitting unit as defined in claim1, wherein the tips of said posts projecting through said apertures insaid inner member are bent over in engagement with the inner surface ofsaid inner annular member.

5. The blade hydrodynamic torque transmitting unit as defined in claim 1wherein said posts are tapered to converge toward their outer ends, saidblade bores forming interior surfaces mating and slidably engaging withthe tapered surfaces of said posts.

6. The bladed wheel defined in claim 1 wherein the corners of saidblades at the intersections with said concave surface are provided withconcave fillets facing into the spaces betweensaid blades. I

7. The bladed wheel defined in claim 1 wherein said posts are slantedwith respect to the direction of wheel rotation,

8. The bladed wheel defined in claim 7 wherein (a) each of said bladesis formed with a here through which its post coaxially extends,

(b) said bore having opposed ends respectively facing said inner annularmember and said outer annular member and respectively containing theexit and entrance to said bore,

(0) said exit and entrance being formed in planes extending at an acuteangle to the axis of said bore to leave portions of each post exposed inthe spaces between said blades.

9. The bladed wheel defined in claim 1, wherein each of said blades isgenerally formed in the shape of a parallelogram in a cross sectioncontained in a plane passing substantially through the longitudinal axisof each of said posts.

10. The bladed wheel as defined in claim 1, wherein (a) each of saidblades in substantially formed in cross section with a shape of aparallelogram having oppositely facing parallel sides,

(h) each of said posts having its longitudinal axis extending inparallel relation to said parallel sides.

11. In the bladed wheel unit defined in claim 1, each post at itsthicker base being formed iwth an inclined side wall facing thedirection of normal rotation of said Wheel unit.

12. In the bladed wheel unit defined in claim 11, said posts beingthinner where they extend through said apertures and .said blades havinggreater wall thickness where they surround said thinner post portions.

13. The bladed wheel defined in claim 11 wherein said blades areenlarged at opposed end regions where said posts enter and leave saidblades.

14. A unitary bladed wheel for a hydrodynamic fluid torque transmittingdevice, said bladed wheel comprising:

(a) separately formed coaxially mounted inner and outer annular bladesupport members forming a generally annular space therebetween;

(b) a plurality of blades fixedly positioned in said annular space andconnected to said members only by separable abutting surfaces which arefree of interlock;

(0) a plurality of integral posts projecting inwardly from said outermember and frictionally through the blades and through apertures in saidinner memher;

((1) means on the inner ends of said posts for securing said members andblades together as a rigid unit with said blades extending rigidlybetween said members and having separable opposite end abutment withsaid members, and

(e) each of said blades being formed substantially as a parallelogram ina cross section with each of said posts entering its respective blade atone corners of 15 16 said parallelogram and leaving said blade at the2,387,722 10/ 1945 Dodge 29-15 6.8 corner diagonally opposite from saidone corner. 2,479,057 8/1949 Bodger 25377 15. The bladed wheel definedin claim 14 wh rein ac 2,494,539 1/ 1950 Bolender 103115 of said bladesis made up from two separately formed sec- 2 497 041 2 1950 Bodger 25377 tions disposed one on each side of each post and secured 5 2,500,7453/1950 Bloomberg 253 77 together to form a hollow boX-hke blade.2,653,547 9/1953 Langdon 103 115 2,690,132 9/1954 Misch 103-1 15References by the Examme' 2,710,580 6/1955 Holzworth 103-115 UNITEDSTATES PATENTS 10 2,786,646 3/1957 Grantham 25377 649,014 5/1900 Terry25377 748,216 12/1903 Rateau et' a1 25377 FOREIGN PATENTS 1,507,1439/1924 Toussaint et a1 230-134 1,185,249 2/ 1959 France- 1 10 7 1934Noack 253 77 720,956 12/1954 Great Britain. 2,304,721 12/1942 Werther103-115 Doran 15 J. Primary Examiner. 2,365,354 12/ 1944 Pennington29-l56.8 JOSEPH H. BRANSON, JR Examiner. 2,371,588 3/1945 Salerni10311'5

1. A BLADED WHEEL UNIT FOR A HYDRODYNAMIC FLUID TORQUE TRANSMITTINGDEVICE COMPRISING: (A) SEPARATE COAXIALLY DISPOSED INTEGRAL INNER ANDOUTER ANNULAR MEMBERS SPACED TO PROVIDE A GENERALLY ANNULAR SPACE OFSUBSTANTIALLY CONSTANT CROSS-SECTION THEREBETWEEN FOR PASSAGE OF FLUID;(B) SAID OUTER MEMBER HAVING AN INWARDLY FACING SMOOTHLY CURVEDTRANSVERSELY CONCAVE ANNULAR INNER PASSAGE DEFINING SURFACE AND SAIDINNER MEMBER HAVING AN OUTWARDLY FACING SMOOTHLY CURVED TRANSVERSELYCONVEX ANNULAR OUTER PASSAGE DEFINING SURFACE OPPOSED THERETO; (C) SAIDINNER MEMBER HAVING A SERIES OF CIRCUMFERENTIALLY SPACED APERTURES; (D)A PLURALITY OF POSTS OF ONE-PIECE CONSTRUCTION WITH SAID OUTER MEMBERAND PROJECTING THROUGH SAID SPACE AND THROUGH SAID APERTURES; (E) APLURALITY OF SEPARATE HOLLOW BLADES MOUNTED ON SAID POSTS WITHIN SAIDSPACE WITH THE INNER AND OUTER ENDS OF SAID BLADES SHAPED TO TIGHTLY ANDSMOOTHLY BUT SEPARABLY ABUT SAID INNER AND OUTER MEMBER SURFACESRESPECTIVELY; (F) COOPERATING COMPLEMENTARY PROJECTION AND RECESS MEANSON EACH OF SAID BLADE AND THE ADJACENT INTERIOR OF SAID OUTER MEMBERDISPOSED RADIALLY OUTWARDLY OF SAID POSTS IN THE UNIT AND ADAPTED FORDIRECT INTERFITTING ENGAGEMENT DURING ASSEMBLY AS SAID POSTS ARE PUSHEDSLIDABLY THROUGH SAID HOLLOW BLADES, SO THAT SAID BLADES ARENON-ROTATABLY MOUNTED AND LOCATED IN DESIRED RELATIVE SPACING ANDORIENTATION WITHIN SAID FLUID PASSAGE SPACE; (G) SAID BLADES HAVING ENDTO END THROUGH BORES FITTING SNUGLY AND SMOOTHLY OVER SAID POSTS SO THATTHE BLADE AND POSTS ASSEMBLIES ARE SUBSTANTIALLY SOLID THROUGHOUT; AND(H) SAID POSTS BEING THICKER AT THEIR BASES WHERE THEY INTERSECT SAIDCONCAVE SURFACE OF THE OUTER MEMBER; AND (I) MEANS ON THE INNER ENDS OFSAID POSTS AND DISPOSED WITHIN AND COACTING WITH SAID INNER MEMBER FORRECURING SAID INNER MEMBER IN BRIDGING RELATION ACROSS SAID INNER ENDSOF ALL OF SAID POSTS FOR AXIALLY HOLDING ALL OF SAID BLADES RIGIDLYBETWEEN SAID INNER AND OUTER MEMBERS AND FASTENING SAID MEMBERS ANDBLADES TOGETHER AS A RIGID UNIT.